I have no reason I just thought they were super cool.

Any of the large cities.

Dallas - Cowboys being America's team, the Stars jerseys with their faint Oakland A's colors, the Mavs with a strong blue, Rangers having that All-American flair

Philadelphia - They have some of the better retro looking uniforms that really reflect the Founding spirit of the city. Flyers, Sixers, Eagles and Phillies having the soaring attitude of patriotism. Now if only their teams would show that on the playing field...

Los Angeles - If you want to find that charter city for Professional Sports on west coast, look no further than our neighbors to the south. LA is a city known for its winners, but it is well known for doing it in style. Purple means royalty, and it can be found on the seats in Staples Center, the Lakers jerseys and NHL's Kings (Although I think they gacked the Purple and Silver duo from Sacramento's Kings). Clippers weren't perennial winners, but they have a sleek Red White and Blue combination going for them. Nobody can steal that trademark Dodger blue and the script "Dodgers" or "Los Angeles" is very Oakland-esque. Angels and Mighty Ducks look very childish, but what can you expect being within walking distance of the magic of the Mouse's house?

Young Flair:

Certain towns may be old, but for the face of their sports franchises, they are quite fresh. Such cities like Denver, Phoenix and Miami feature teams that have had moderate success, but I think they look much better in uniforms than on the field.

Miami has tropical colors from the Marlins and Dolphins, while the Panthers and Heat bring rage in their unis.

Denver still can't wipe away the spirit of the Nordiques with a cartoony foot, a Bronco can be blue and orange, a Nugget rather baby Blue, and they Tap the Rockies with the purple mountain majesty on their logo.

Phoenix just screams desert in all of their sports. Coyotes, Snakes, Cardinals and the Sun itself burn brightly on the playing field.

Not sure which one has the best jerseys overall, but there are a lot of cities to choose from...

With the Rivercats, Yard Dawgs, Blazers, Hornets, Sonics (which I think will be converted to the drive thru logo), Storm, and oh yeah barely making the cut are those guys a little south in Norman (put the names back on the jersey already)

had nice, understated uniforms.  And I dig the Marlins' teal color, but that just may be because I am gay.

Best uniforms of all time, though?  Easy.

1973 Oakland Athletics.

It's hard to imagine this conversation without mentioning Pittsburgh. Each of the major sports franchises wear black and gold.

Silver and Black, Green and Gold, and.... yeah, maybe another city.

..I'm going to go with Minnesota.

Admittedly, I'm not huge on the Twins' uniforms, but the Minnesota Vikings have the greatest helmets (and colors) in all football, while the Timberwolves have great shirts, and the Minnesota Wild have my favorite look and logo in hockey circles. They just look like hermit timbermen in that dark green gear - it's a great theme.

the tigers have a nice classic look with the old english "D".

The lions have uniform schemes simple enough to look classic.  

The red wings, well, That wheel ties in with the city.

I am drawing a blank on the pistons though....

As with many here I love the classic strong lines and colors.  

Were it not for the hideous Marlins ensembles I'd nominate Miami as a contender.   The Dolphins and 'Canes especially sport looks which plainly say "this is us," especially at home.  The Heat have a decent set of unis too, in a modern NBA sense.  But the Marlins, ye gads...

most conservative uniforms in American sports.  The Red Sox uniforms look like they did back when Dom Dimaggio and Ted Williams roamed Fenway (after the obligatory interruption for pull-overs and brightly-colored caps in the 70s).  The Bruins still wear the old-fashioned "B".  And the Celtics still wear the white-with-green at home and green-with-white on the road.

The Patriots, though...they've changed, and the unis are pretty ugly, IMHO.

SF demons

gets my vote: Toronto.  The Maple Leafs, heated rivals of my team the Sabres though they are, have the best uniforms in hockey.  The Blue Jays can't seem to settle on a logo for their hat, but their uniforms are consistently good (though the current ones aren't quite up to par with the great ones from their championship years...had to love the, uh, double lines of the numbers, and the shade of blue.  The Raptors are the worst of the three, but they're decent, thanks primarily to the fact that they're of the more sleek fabric and jersey cut style (kind of glossy, looks like satin or something, with more fabric on the shoulder...not just thin straps) that only certain teams wear: offhand, I can think of them, the Heat, the Pistons, the Lakers, and the Mavs wearing that style.  I think they were originally made by Nike, but I know the Mavs' are actually Sean John, so I'm not quite sure which company/companies are responsible for which jerseys.

for me the worst qualifiers are the state of Washington (Seattle) and the city of Washington.  The M's uniforms are pretty good, but the Seahawks and especially the Sonics make me wish that red-green colorblindness didn't skip a generation (my father has it).  Overall, I give the slight edge to DC for having the worst uniforms though...never liked the Redskins', and the Wizards' and Caps' unis need to go retro permanently; trade in the turquoise for the red, white, and blue, please.  The Nats' aren't that great either thanks to the grey, though I liked the red ones they were wearing today as Ramon Ortiz pitched like Clemens and hit like Pujols.

Ravens' and Jaguars' alternate black jerseys...Raiders' too, not quite as good as the other 2
Bills' pre-2000
A's--classic
Oregon football (love them or hate them)
Da U's football and basketball
Duke basketball, UNC basketball
St. John's basketball, when Artest was there, before they took the names off them...them, Cal, and Cincy were the college basketball teams wearing His Airness, and they were all sweet, but St. John's were the best